code: def test_forward_gpu(self):
      self.check_forward(
          cuda.to_gpu(self.x),
          cuda.to_gpu(self.t),
          cuda.to_gpu(self.W),
          cuda.to_gpu(self.samples),
      )
  
file_path: chainer/tests/chainer_tests/functions_tests/loss_tests/test_black_out.py
imports: import unittest
  import numpy
  import chainer
  from chainer.backends import cuda
  from chainer import functions
  from chainer import gradient_check
  from chainer import testing
  from chainer.testing import attr
  from chainer.testing import condition
label_desc: Use image node_id 4 for calling the TestBlackOut obj's underlying member method code with example usage: obj.test_forward_gpu() without return types